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排序方式: 共有617条查询结果,搜索用时 0 毫秒
611.
612.
AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two weeks.The ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent extracts.Fractionation of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1... 相似文献
613.
G Merino R Real MF Baro L Gonzalez-Lobato JG Prieto AI Alvarez MM Marques 《Drug metabolism and disposition》2009,37(1):5-9
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates. 相似文献
614.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献615.
Rearrangement and overexpression of the BCL-1/PRAD-1 gene in intermediate lymphocytic lymphomas and in t(11q13)-bearing leukemias 总被引:7,自引:0,他引:7
Rimokh R; Berger F; Delsol G; Charrin C; Bertheas MF; Ffrench M; Garoscio M; Felman P; Coiffier B; Bryon PA 《Blood》1993,81(11):3063-3067
The t(11;14)(q13;q32) translocation and its molecular counterpart, BCL- 1 rearrangement, are consistent features of intermediate lymphocytic lymphoma (ILL). Rearrangement is thought to deregulate the nearby PRAD- 1/BCL-1 proto-oncogene that is a newly identified member of the cyclin family. To characterize further the association between rearrangement of chromosome 11q13 and over-expression of BCL-1. Southern blot analysis was performed in 33 cases of ILL, 5 cases of t(11;14)- associated leukemias, and 1 case of leukemia carrying a variant translocation t(11;19)(q13;q13) using three separate BCL-1 locus probes. When RNA was available, BCL-1 expression was assessed by Northern blot analysis. DNA from 19 of 33 ILL (57%) showed BCL-1 rearrangement, 16 involving the major translocation cluster (MTC) region and 3 involving a new breakpoint cluster located in the 5' flanking region of the BCL-1 gene. DNA from 3 of 6 t(11q13)-associated leukemias demonstrated a rearrangement involving the MTC. Northern blot analysis showed that BCL-1 was overexpressed in 14 of 15 ILL and in all leukemias analyzed (included the t(11;19) leukemia) relative to normal and malignant lymphoid tissues. These results constitute additional elements in favor of the role of BCL-1 in lymphoid neoplasia and allow us to speculate about its mechanisms of activation. 相似文献
616.
背景:经高温处理的煅烧骨具有类似自然骨的连续微孔结构,良好的生物相容性和降解性。
目的:观察牛煅烧骨的生物相容性、细胞相容性及毒性。
方法:①细胞相容性实验:将牛煅烧骨与第3 代已诱导的Wistar大鼠骨髓间充质干细胞复合培养。②溶血实验:将煅烧骨浸提液、生理盐水与双蒸水加入兔血中。③凝血实验:将煅烧骨加入兔血浆中。④急性毒性实验:在昆明种小鼠尾静脉分别注射煅烧骨浸提液、生理盐水。⑤微核实验:在小鼠腹腔分别注射煅烧骨浸提液、生理盐水与环磷酰胺。⑥局部刺激性实验:将煅烧骨浸提液、生理盐水分别注射于兔两侧脊柱皮下。⑦热源检测实验:在兔耳静脉注射煅烧骨浸提液。⑧皮下植入实验:将煅烧骨材料植入Wistar大鼠背部皮下。
结果与结论:煅烧骨材料无细胞毒性,具有良好的细胞及血液相容性;对皮肤、肌肉无刺激作用;对心、肝、肾重要器官无毒性作用;皮下植入后对周围组织无刺激作用,能够部分降解吸收并被机体组织替代;无致热作用,对凝血功能无影响,对小鼠骨髓细胞无抑制及毒性作用。 相似文献
617.
In daily clinical practice, patients are frequently asked about their swallowing as part of the patient-clinician interview. This study compares the diagnostic performance of a single open question ‘What about swallowing?’ (usual care) with the Eating Assessment Tool (EAT-10) as reference test in screening for oropharyngeal dysphagia (OD). 303 outpatients at risk of OD were recruited at three university hospitals: 162 men and 141 women with a mean age of 70 years. All data were retrieved by phone. To identify patients at risk of dysphagia, two different cut-off scores for the EAT-10 total score were retrieved from the literature. The diagnostic performance of the single question was determined by comparing dichotomized answers to the single question (no problems versus difficulties in swallowing) with the EAT-10 as reference test. Sensitivity, specificity, positive and negative predictive values ranged between 0.75–0.76, 0.75–0.84, 0.93–0.97 and 0.38–0.43, respectively. Mostly, the results of this exploratory study indicate a sufficient diagnostic performance of the single question in identifying patients who are at risk of dysphagia when using the EAT-10 questionnaire as a reference test. Further research, is, however, necessary to provide additional psychometric data on Functional Health Status (FHS) questionnaires including the single question using either FEES or VFS as gold standard or reference test. 相似文献